1. Field of the Invention
The field of the invention relates to a power controller system, in particular to a power controller system which is protected from lightning strikes or fault conditions for example.
2. Description of Related Art
Traditionally a power controller system includes a switching device such as an electro-mechanical switch to interrupt the supply of electrical power to a load in the event of a lightning strike or fault condition. However, in order to try to provide faster reaction times and reduce the size and cost of switching devices, faster operating devices are being used such as micro-electromechanical switches (MEMS) and transistors, such as MOSFETs. Although these devices are faster in operation, their size is proportional to the fault transient that they can accommodate. As they generally have a relatively low thermal mass, they can only accommodate a limited fault transient.
In aviation applications, such as in an aircraft, it is important that a fault condition or lightning strike does not interrupt the current to a given load which may be crucial to the aircraft such as, for example, cockpit controls and instruments, landing gear, engine control, environmental systems etc. Furthermore, electrical power distribution in the aviation industry is moving to higher and higher voltage architectures such that the fault current and environmental considerations such as lightning strikes are becoming more and more severe. Traditionally the power distribution system is over engineered, for example with the transistor switch being much larger to he able to absorb such events as lightning strikes and faults without interrupting the load during such transients. However, over engineering the power distribution system and switches increases cost, size and weight, reducing an aircraft's range and increasing its fuel consumption.